Method and apparatus for controlling a lens, and camera module incorporating same

Abstract

An efficient image capture system is disclosed that integrates functions to control a lens including one or more of focus or object distance, zoom, temperature compensation, and stabilization within an image signal processor (ISP) with appropriate algorithms. In particular, the integrated ISP circuitry may control the motion of the focus and zoom optics of an optical assembly, control stabilization, control the flash, provide enhanced functions and features for controlling the zoom and focus lenses to enable enhanced image capture sequences and / or tracking lens data, provide a set of algorithms within the ISP to alter the aspect ratio (both height and width of an image) of the image, for example to compensate for the addition of an anamorphic lens, and integrate an anamorphic lens into the module to alter an image's projected aspect ratio onto the focal plane array.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 60 / 604,525, filed on Aug. 25, 2004, the contents of which are incorporated by reference herein.FIELD OF THE INVENTION [0002] The present invention relates, generally, to an image capture system, and in particular embodiments, to an image capture system that integrates functions within a lens module, including some of all of the following: lens groups, lens motor drives, focal plane array, Image Signal Processor (ISP), control of focus or object distance, zoom, flash, shutter, temperature compensation, and / or stabilization. BACKGROUND OF THE INVENTION [0003] Conventional imaging systems (e.g. digital cameras, camera phones, camcorders and other imaging devices and applications) typically incorporate a camera lens module as part of the system assembly. This lens module is comprised of a focal plane array, a mechanical housing, an optics assembl...

AI Technical Summary

Benefits of technology

[0020] Embodiments of the present invention are directed to a modular image capture system that improves manufacturability (i.e. reduces manufacturing time, expense, and number of assembly errors) by integrating functions within a lens module, including some or all of the following: auto-focus and zoom lens groups, lens motor drives, focal plane array, ISP, control of zooming and focus or object distance, flash, shutter, temperature compensation, image stabilization, and a distance / focus measurement device (for non-image based focus control), including the appropriate algorithms. The integration of functions also improves image acquisition time and decreases imaging device size, weight, and power consumption.

[0026] The integrated approach provides certain benefits, as mentioned above. For example, the shot-to-shot time can be decreased by integrating the ISP and the focus control algorithm together on the same chip. Integrating the drive electronics, feedback devices, control signals, and other relevant lens control electronics as well as the flash within the module assembly reduces the amount of electrical interconnects to the module from the system and can reduce overall system size and power consumption.

Problems solved by technology

Because conventional imaging systems utilize a lens module 100 separate from the devices that generate control signals, such as the lens drive electronics 120 illustrated in FIG. 1, additional manufacturing steps are required to assemble and connect the lens module together with these associated devices, increasing the time and expense of manufacture.

In addition, these extra steps increase the chance of assembly errors.

Having lens modules separate from devices that generate control signals, such as the lens drive electronics, can also create performance issues.

The generation of the control signals outside the module wastes system power because of the extra processing steps performed by the devices outside the module.

Having lens modules separate from devices that generate control signals, such as the lens drive electronics, can also lead to undesirable product specifications and operational parameters.

For example, the use of separate circuits (e.g. chips) for the lens drive electronics adds extra components, which can lead to increased imaging device size and weight.

In addition, the use of separate circuits may require that each circuit be separately powered, with higher-powered output buffers used to drive signals between chips, resulting in increased power consumption.

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